Sanding attachment



y 22, 1956 J. P. HOLLINGSWORTH 2,746,216

SANDING ATTACHMENT Filed May 12, 1953 Fig.

Fig. 3

Jean P. Hall/'ngsworfh INVENTOR.

BY wdWa/way 5m United States Patent Oflice 2,746,216 Patented May22,1956

SANDING ATTACHMENT Jean P. Holliugsworth, Savannah, Ga.

Application May 12, 1953, SerialNo. 354,453

1 Claim. (Cl. 51-195) This invention relates in general for sandingattachments to be utilized in conjunction with portable sanding toolsand pertains more particularly to an improved form of sanding member.

A primary object of this invention is to provide an improved form ofsanding attachment which incorporates a sheet of flexible material ofnon-circular configuration whereby the circumferential portion of theattachment is formed in interrupted fashion, that is, the circumferenceof the member is formed with radial projections thereon.

Another object of this invention is to provide a sanding attachmentconstructed in accordance with a predetermined pattern to endow the samewith the following characteristics 1. The attachment is self cleaninginasmuch as its circumferential portion intermittently engages againstthe surface which is to be sanded.

2. The attachment, by virtue of its interrupted circumferentialformation, enables a user of the attachment to have visual access to aportion of the surface which is being sanded.

3. The standing member, being formed with radially projectingcircumferential portions, will readily permit flexing of itscircumferential portions to conform in shape with the object to besanded.

The attachment will, by virtue of its interrupted abrading action,obviate the formation of grooves or scratches in the surface beingsanded and will, in general, provide a more uniform sanding operation.

These together with other objects and advantages which will becomesubsequently apparent reside in the details of construction andoperation as more fully hereinafter described and claimed, referencebeing had to the accompanying drawings forming a part hereof, whereinlike numerals refer to like parts throughout, and in which:

Figure 1 is a front elevation showing a portion of a vehicle with thenovel sanding attachment utilized in conjunction therewith;

Figure 2 is a plan view of the sanding attachment and showing in dottedlines the manner of its sanding operations; and

Figure 3 is a transverse section taken substantially along the plane ofsection line 3-3 of Figure 2.

Referring now more particularly to Figure 1, reference numeral 19indicates generally a portable grinder or sanding tool which is shown asof the electrically driven type and which includes a stub drive shaft 12provided with the attaching washer and nut assembly 14, which isengageable within a central aperture 16 in the sanding attachmentindicated generally by the reference character 18. Numeral 20 indicatesgenerally the hood of a car while the reference character 22 indicatesgenerally the fender thereadjacent and Figure 1 indicates the manner ofutilizing the sanding attachment in conjunction with surfaces of both ofthese vehicle members.

Referring now more particularly to Figures 2 and 3,

2. reference numeral22 indicates the-main or central portion of thesanding-attachment within which the aperture 16 is providedandnumeral 24indicatesthe peaked projections extending radially outwardly of thiscentralportion, such projections being formed by virtue of the fact thatthe sanding attachment is polygonal in configuration, although it is tobeunderstoodthat other and different shapes than the hexagonalconfiguration shown may be utilized with advantage. The-material ofwhich the sanding attachmentis. formed may be of any suitable commercialform. and. contemplates not only the use of a resilient backing plateprovided with conventional sand paper secured to the outer surfacesthereof but also contemplates the use of the bonded type of abrasivematerial in which the abrasive is embedded throughout the entire bodyportion.

Referring now most particularly to Figure 2, it will be seen that thearea which is sanded when the attachment is rotated will be circular innature and will include those peripheral portions indicated generally bythe reference numeral 26 and it will be appreciated that these portionsform sectors of the circular area being sanded. Due to the rotation ofthe sanding attachment, an annular outer circumferential portion of thearea sanded receives intermittent and sequential abrading actions bysuccessive projection portions 24, this intermittent abrading actioneffecting the above described novel characteristics which enable theattachment to operate in the manner intended.

Considering the self-cleaning characteristic of the attachment, it willbe noted that the radial projections extending from the main centralportion of the sanding attachment will allow material engaged with theabrasive material to Work along the surface thereof until it has reachedone of the edges 28 of the attachment and at this point such foreignmaterial will be allowed to escape from the abrasive surface of theattachment. This will also tend to obviate the formation of deepscratches or grooves in the surface being sanded inasmuch as thesegrooves are normally formed by the abrasive material picking upparticles torn from the metallic surface being sanded and carrying themalong to gouge the surface of the metal. It will be readily appreciatedthat both of these characteristics are not present in the conventionalform of circular sanding disks. Each individual path of movement on suchdisks defines a continuous circle which both prevents the abovedescribed cleaning operation and allows gouging of the metallic surface.

Furthermore, the over-all sanding action of the polygonal attachmentshown will be far superior in its annular circumferential area thanconventional circular sanding disks inasmuch as the intermittentabrading action by the radial projections will cancel out the minutescratches in the metallic surface of preceding projections, such notbeing the case in the use of circular disks inasmuch as these memberswill tend to establish a definite pattern of sanding operation forming adistinctive swirling lines of abrasion on the metallic surface.

Insofar as the visual aspect of the invention is concerned, it will benoted that the action of the projections 24 is much the same as isencountered in the case of rotating fan blades, that is, the surfacebeing sanded beneath the projections is readily seen during the sandingoperation so that the proper amount of abrading can be easily obtained.

In view of the foregoing, it will be readily appreciated that thepreferred manner of utilizing the sanding attachment is to engage onlyits peripheral or circumferential portion against the surface to besanded, the resultant sanding action by this particular portion of theattachment allowing the entire surface to be sanded to derive thebenefits of the particular configuration of the attach- 3 1 ment asnoted above. However, the device may be utilized in the manner shown inFigure 1 wherein a substantially circular area is sanded.

From the foregoing, the construction and operation of the device will bereadily understood and further explanation is believed to beunnecessary. However, since numorons modifications and changes willreadily occur to those skilled in the art, it is not desired to limitthe invention to the exact construction shown and described, andaccordingly all suitable modifications and equivalents may be resortedto, falling within the scope of the appended claim.

What is claimed as new is as follows:

,A sanding tool comprising a rotary shaft and a disk of abrasivematerial having a center portion attached to said shaft for rotation ofthe disk about its axis by said shaft, said disk having a polygonal edgeforming a plurality of straight peripheral edge portions and tipsalternating with said edge portions, said edge portions and tips beingof the same thickness, said disk from its center portion to said edgeportions and tips being free and selfsupporting, said disk beingflexible radially and axially for conforming to a concave surface tofacilitate sanding by said edge portions and tips.

References Cited in the file of this patent UNITED STATES PATENTS178,398 Barker June 6, 1876 1,156,958 Whitin Oct. 19, 1915 1,353,967Lorenz Sept. 28, 1920 1,587,843 Koreneif June 8, 1926 1,938,520 DrapakDec. 5, 1933 2,146,548 Mitschang et al. Feb. 7, 1939

